gebbert



Aug. 28, 1928. 1,682,121

A. GEBBERT HIGH FREQUENCY OSCILLATION SYSTEM FOR MEDICAL APPARATUS Filed Nov. 9, 1 926 Patented Aug. 28, 1928.

I UNITED STAT S ARTHUR GEBBERT, or ERLAivGEN, GERMANY.

' HIGH-FREQUENCY OSCILLATIONSYSTEE For: iuEnioa ArrAaATnsI Application filed November 9, 1926, Serial No. 1 11355 and Germany beceniber This invention relates to improvements in electrical systems for the production of hlgh frequency oscillations, and has particular reference to a system of this type to be used- 6 for medical purposes. 1

Systems that serve for the production of high frequency electrical oscillations for medical purposesmay be protected from in jurious heating in case of slight consumption 10 of energy or an absence thereof by connecting in parallel with the source of high frequency or the consumption circuit, or a partthereof, a loading resistance and a variable self-induction, the latter, however, only when any self-i'nductionthat may be connected in series with the patient has been switched oif. By means of suitable dimensioning of the self-induction coil or coils, there may be made to flow in the circuit including the patient only a weak current which, however, cannot be caused to disappear and which, at the removal of the electrodes from the patient during an operation, still continues to produce weak sparks. o

In accordance with the invention, the above difficulty is overcome by connecting a variable self-induction in parallel with a series connection consisting of a loading resistance and the patient with the movable part of the regulating device connected between the patient and the loading resistance.

The inventive idea involved is capable. of receiving a variety of expressions, some of which, for the purpose of illustrating the invention, are shown in the accompanylng drawing; but it is to be expressly understood that said drawing is to be used merely for the purpose of facilitating the description of the invention as a whole and not to define the limits thereof, reference being had to the appended claims for this purpose.

In the drawing- Figure 1 is a diagrammatic illustration of a system embodying one form of the invention; and I Figure 2 is a similar view illustrating another form.

In the form of the invention shown in Figure 1 there is provided, in parallel with the.

secondary winding of a transformer supply-- ing high frequency current a, the self-induction coil 1;. To the two ends of the coil 12 there are connected in series the electrodes 0 and the loading resistance d, theelectrodes u beingadapted to be applied to a patient ance h and other electrode z.

the element 6 toward the right results in greater amperage in the'electrode circuit and 'a'movement thereof toward the left causes a short-circuiting of said electrodes. In the latter position of the element 6 the electrodes maybe taken from the patient while the apparatus is in full operation without encountering the previously mentioned drawback. As many pieces of apparatus as desired, including the elements 6, c, d and 6 may be connected to the source a in parallel.

As illustrated in Figure 2 the system may also be arranged for use with two or more patients by the employment of a common loading lamp or resistance. In this case the high frequency current flows from the secondary of the transformer f successively through the electrode 9, the common resist- In parallel with the resistance 71 and with each one of the electrodes g'and a there are located the va-' to the full potential or is short-circuited.

Since in the latter case there is always presenta path for the high frequency current which is free from induction it is possible, in this case also, to remove the electrodes from the patient while the apparatus is in full operation without the occurrence ofthe sparking previously mentioned.

The system renders possible, as is apparent, a corresponding extension for more than two patients if distributor resistances are connected to the terminals 9, i, or several pieces of the apparatus, including the elements 9, h,

i, is, m, n, 0 are connected in parallel.

What is claimed is: 1. In an electrical system for the control of high frequency oscillations especially used a the circuit between trodes.

2. Ina-n electrical system for the control of high frequency oscillations especially used in medical apparatus, the combination of a high frequency transformer, a variable selfsaid resistance and elecinduction in parallel therewith. and including a regulating element, and a loading resistance and electrodes connected in series with said induction, said regulating element being connected to the circuit between said resistance and electrodes,

3. In an electrical system for the control of high frequency oscillations especially used in medical apparatus,vthe combination of a high frequency transformer, a plurality of variable self-induction coils connected in parallel with said source and each having a regulating device, a plurality of electrodes in circuit with said coils, and a common loading resistance in series with said regulating de vices.

v -ARTHUR GEBBERT. 

